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Resistance to those pathogens that cause root rots, white mold, and common bacterial blight (CBB) is only partial and is usually under large environmental effects. The partial resistance is quantitative in nature and QTL analysis is used to measure the size (effect) and chromosomal location of each locus that contributes to the overall resistance (Vasconcellos et al. 2017). Complete resistance is not possible to achieve, as many environmentally sensitive QTL contribute to resistance, and a large number of QTL need to be accumulated to provide effective resistance. Limited progress in breeding for resistance to these diseases has been reported, with the exception of CBB (Singh and Miklas 2015), where QTL with major effects have been identified (Viteri et al. 2014) and combined to achieve high levels of CBB resistance. The transfer of two major QTL from tepary to common bean is a major success story for interspecific hybridization using embryo rescue methods (Thomas and Waines 1984). The two major QTL exhibit recessive epistasis, and when combined confer a high level of resistance to CBB in common bean (Vandemark et al. 2008). A combination of single gene resistance to individual races (Miklas et al. 2014) with QTL conferring resistance to most races (Tock et al. 2017) has been used to breed for resistance to halo bacterial blight.